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- A power management strategy for a stand-alone photovoltaic/fuel cell energy system for a 1kW applicationPublication . Pinto, P.J.R.; Rangel, C. M.In this paper a power management strategy is presented for a stand-alone photovoltaic (PV)/fuel cell (FC) energy system. PV is the primary power source of the system and an FC-electrolyzer combination is used as a backup and a long-term storage system. The energy in the hybrid system is balanced by the common dc bus voltage regulation. A simple hysteresis voltage control is used for dc bus voltage regulation. In this way, the fuel cell and the electrolyzer can be protected from unnecessary utilization or irregular operation (reduction of frequent start-ups and shutdowns). Simulation results obtained using Matlab and Simulink are presented to verify the effectiveness of the proposed control algorithm.
- Simulation of a stand-alone residential PEMFC power system with sodium borohydride as hydrogen sourcePublication . Pinto, P.J.R.; Sousa, T.; Fernandes, Vitor; Pinto, A. M. F. R.; Rangel, C. M.Catalytic hydrolysis of sodium borohydride (NaBH4) has been investigated as a method to generate hydrogen for fuel cell applications. The high purity of the generated hydrogen makes this process a potential source of hydrogen for polymer electrolyte membrane fuel cells (PEMFCs). In this paper, a PEMFC power system employing a NaBH4 hydrogen generator is designed to supply continuous power to residential power applications as stand-alone loads and simulated using Matlab/Simulink software package. The overall system is sized to meet a real end-use load, representative of standard European domestic medium electric energy consumption, over a 1-week period. Supervisory control strategies are proposed to manage the hydrogen generation and storage, and the power flow. Simulation results show that the proposed supervisory control strategies are effective and the NaBH4–PEMFC power system is a technologically feasible solution for stand-alone residential applications.
- The H2Excellence Project: Fuel Cells and Green Hydrogen Centers of Vocational Excellence towards affordable, secure, and sustainable energy for Europe [Resumo]Publication . Gano, António; Pinto, P.J.R.; Esteves, M. Alexandra; Rangel, C. M.ABSTRACT: The demand for green hydrogen (H2) and related technologies is expected to increase in the coming years mainly framed by drivers such as climate change and energy security of supply amid the European and global energy crises. REpowerEU Plan called for an intensification of hydrogen delivery targets, that will bring large-scale adoption of hydrogen production and applications in various sectors, stressing the need for a skilled workforce in the emergent hydrogen markets. To that end, the Erasmus+ European H2Excellence transnational project[2] has gathered 24 partners across the EU, to establish a Platform of Vocational Excellence in the field of fuel cells and green hydrogen technologies, with an educational and training offer that will tackle identified skill gaps and implement life-long learning opportunities. The project aims to become a benchmark in training and knowledge transfer, contributing to the integration of quality employment into green hydrogen local innovative systems approaching the entire hydrogen value chain.
- Performance of a solar-hydrogen stand-alone system for residential applicationsPublication . Pinto, P.J.R.; Rangel, C. M.Hydrogen, as an energy storage medium, is considered a promising solution to overcome the limitation of intermittent renewable energy sources. In this paper, a residential scale solar-hydrogen based stand-alone energy system is designed, modelled and the simulated system performance under real end-use load, representative of standard European domestic electrical energy consumption, and meteorological conditions is analyzed. The sun is the primary energy source of the system and a fuel cell-electrolyzer combination is used as a backup and a long-term storage system. A battery bank is also used as energy buffer and for short time storage. Matlab/Simulink® is used for the overall system modelling and simulation. The results show that the designed solar-hydrogen system is in principle capable of operating autonomously and in a sustainable manner. The designed system is able to convert 7.6% of the total energy irradiated in one year.
- Potential for hydrogen production associated to water and food in off-grid communities of Southern AfricaPublication . Rodrigues, Luiz; Araujo, Luis; Gano, António; Pinto, P.J.R.; Simoes, Sofia; Brito, Paulo; Monjane, Armindo; Rangel, C. M.ABSTRACT: Solar energy is called to meet electricity demands for isolated, off-grid communities in Africa. However, solar electric energy is intermittent and can be stored, for a limited amount of time, in batteries, which are expensive and cause serious environmental impacts at the end of their lifetime. Conversion of the surplus electric energy to green hydrogen through water electrolysis and back to electricity, when needed, using electrolyser-fuel cells systems, is examined as a potential solution to meet the water-energy-food nexus in Southern Africa. In the framework of the Agrivoltaics concept, the main constrains, opportunities and parameters to consider its applicability are presented and discussed, in terms of its technical, economic, environmental and social impacts. In the second phase of this work the developing of a PEM electrolyser for connection to a solar PV power source and a fuel cell device, for a stand-alone application, is proposed, ensuring high reliability and energy conversion efficiencies, as well as adequate transient response and a competitive cost. It is intended as a low-carbon energy system, realising the potential for synergy in the Agrivoltaic concept, aligned with global and regional sustainability goals.
- Distribuição do consumo de eletricidade na indústria no território em Portugal Continental e a potencial satisfação desta procura por fonte solar fotovoltaicaPublication . Barbosa, Juliana; Simoes, Sofia; Oliveira, Paula; Patinha, Pedro; Quental, Lídia; Catarino, Justina; Simões, Teresa; Rodrigues, Carlos; Pinto, P.J.R.; Cardoso, João P.RESUMO: Este documento descreve o trabalho desenvolvido pelo LNEG com vista ao mapeamento do consumo de eletricidade na indústria em Portugal Continental e a potencial satisfação desta procura por energia solar fotovoltaica. O presente estudo derivou do esforço anterior para a identificação no país de áreas com menor sensibilidade (ambiental e patrimonial) para a instalação de centrais de geração de eletricidade de fonte renovável e ampliou o seu âmbito para a investigação da potencial satisfação do consumo industrial de eletricidade em áreas artificializadas para fins industriais e nas áreas envolventes destas consideradas menos sensíveis. A implementação de tecnologias de conversão de energia de fonte renovável de forma distribuída em ambiente construído/artificializado é fundamental para o país. No entanto, a análise pormenorizada desse universo necessita de mais tempo e recursos do que os disponíveis neste âmbito. Neste documento é apresentada uma análise exploratória da integração de sistemas solares fotovoltaicos na indústria, considerando o território por ela ocupado. Deve notar-se que os resultados apresentados traduzem a situação à data de janeiro / fevereiro de 2023, sendo que muita da informação utilizada tem um caráter dinâmico pelo que os resultados deste trabalho enquadram-se num contexto temporal definido, necessitando de atualizações periódicas.
- Identificação de áreas com menor sensibilidade ambiental e patrimonial para localização de unidades de produção de eletricidade renovávelPublication . Simoes, Sofia; Quental, Lídia; Simões, Teresa; Catarino, Justina; Rodrigues, Carlos; Patinha, Pedro; Pinto, P.J.R.; Azevedo, Pedro; Picado, Ana; Cardoso, João P.; Barbosa, Juliana; Oliveira, PaulaRESUMO: Este documento descreve o trabalho desenvolvido pelo LNEG com vista à futura identificação de “Go-To Areas” para a localização de unidades de produção de energia de fonte renovável em Portugal Continental. O trabalho decorreu no âmbito de um Grupo de Trabalho informal, coordenado pelo LNEG e envolvendo as seguintes entidades: a Agência Portuguesa do Ambiente (APA), a Direção Geral de Energia e Geologia (DGEG), a Direção Geral do Território (DGT), o Instituto da Conservação da Natureza e das Florestas (ICNF) e a Direção-Geral do Património Cultural (DGPC). Neste âmbito, pretendeu-se identificar no país as áreas com menor sensibilidade (ambiental e patrimonial) que possam vir a ser elegíveis para um processo de licenciamento mais simplificado para unidades de produção de energia de fonte renovável solar e eólica, permitindo deste modo acelerar a implementação sem comprometer outros valores ambientais e territoriais. As áreas resultantes serão áreas preferenciais do ponto de vista de simplificação do processo de licenciamento, mas não são exclusivas. Ou seja, as áreas aqui identificadas e as futuras “Go-To Areas” que possam vir a surgir não representam os únicos locais do país onde é possível implementar unidades renováveis. No resto do território a implementação é possível, de acordo com o normal processo de licenciamento. Este trabalho não delimita “Go-To Areas” renovável. Trata-se de um documento técnico que apresenta áreas sem condicionantes de exclusão que podem vir a ser consideradas para a definição formal de “Go-To Areas”. Deve notar-se que os resultados apresentados traduzem a situação à data de novembro / dezembro 2022, sendo que muita da informação utilizada tem um caráter dinâmico pelo que este trabalho deverá ser atualizado periodicamente.Este documento é complementado com vários ficheiros eletrónicos do Sistema de Informação Geográfica (SIG) contendo os dados de suporte produzidos/compilados. Por fim e não menos importante, este primeiro trabalho foca exclusivamente as áreas não artificializadas. Embora seja fundamental para o país a implementação de renováveis de forma distribuída em ambiente construído/artificializado, a análise desse universo necessita de mais tempo e recursos do que os disponíveis neste âmbito.
- Analysis of a stand-alone residential PEMFC Power system with sodium borohydride as hydrogen sourcePublication . Pinto, P.J.R.; Fernandes, Vitor; Pinto, A. M. F. R.; Rangel, C. M.Catalytic hydrolysis of sodium borohydride (NaBH4) has been investigated as a method to generate hydrogen for fuel cell applications. The high purity of the generated hydrogen makes this process an ideal source of hydrogen for polymer electrolyte membrane fuel cells (PEMFCs). In this paper, the possibility of using a NaBH4-based hydrogen generator with a PEMFC for stand-alone residential use is examined. A complete model of the system is developed, based on models taken from literature with appropriate modifications and improvements. Supervisory control strategies are also developed to manage the hydrogen generation and storage and the power flow. The operation and performance of the integrated system over a one-week period under real loading conditions is analyzed through simulation. Finally, results of the analysis are summarized and the limitations/further scope are indicated.
- Como o consumo de eletricidade na indústria está distribuído no território em Portugal continental [Comunicação oral]Publication . Barbosa, Juliana; Simoes, Sofia; Oliveira, Paula; Simões, Teresa; Rodrigues, Carlos; Catarino, Justina; Cardoso, João P.; Pinto, P.J.R.; Quental, Lídia; Patinha, Pedro
- Potential for hydrogen production associated to water and food in off-grid communities of Southern Africa [Resumo]Publication . Rodrigues, Luiz; Araujo, Luis; Gano, António; Pinto, P.J.R.; Simoes, Sofia; Brito, Paulo; Monjane, Armindo; Rangel, C. M.ABSTRACT: Solar energy is called to meet electricity demands for isolated, off-grid communities in Africa. However, solar electric energy is intermittent and can be stored, for a limited amount of time, in batteries, which are expensive and cause serious environmental impacts at the end of their lifetime. Conversion of the surplus electric energy to green hydrogen through water electrolysis and back to electricity, when needed, using electrolyser-fuel cells systems, is examined as a potential solution to meet the water-energy-food nexus in Southern Africa. In the framework of the Agrivoltaics concept, the main constrains, opportunities and parameters to consider its applicability are presented and discussed, in terms of its technical, economic, environmental and social impacts. In the second phase of this work the developing of a PEM electrolyser for connection to a solar PV power source and a fuel cell device, for a stand-alone application, is proposed, ensuring high reliability and energy conversion efficiencies, as well as adequate transient response and a competitive cost. It is intended as a low-carbon energy system, realising the potential for synergy in the Agrivoltaic concept, aligned with global and regional sustainability goals.